Hi, what are the impacts of enabling compression on an SSD. How does it affect performance/life span/does it make a difference? thanks!
Pointless on your Agility 3. The SandForce controller natively compresses stuff down on the fly to fit stuff on the drive. So it'd make little difference to your storage space either way. (Check the "Size on disk" on a non-compressed file, should be smaller) All it would do, in theory, is slow down the write & read performance as the CPU has to jump in and compress it all down, or decompress it first.
That's not entirely true... When a SF compresses data on the fly, it does not create more user space - but instead reduces the amount of nand written to &, as a result of this, increases the write speed... ...the latter of which is why highly incompressible writes are slower than highly compressible ones. So, if you enabled NTFS file compression on a SF, it will give the same extra user space as on any other SSD. Having said that, despite the Tom's Hardware article (which i assume is where the question's originated from) i personally wouldn't recommend it at all - both as it is liable to give an overall slowdown on any SSD &, in the case of the SFs, it's possible it may increase the actual quantity of writes to the nand, reducing the lifespan. in the latter case, whilst i don't have access to SF's compression algorithm or their tool for looking at the actual quantity of nand used, more generally there 'can' be issues with re-compressing compressed data... ...well, afaik, NTFS compression by itself can make compressed files like jpegs, rars, mp3s, wmvs, etc both slower &, at times, larger than they started out being. Also, on face value, i think there may be a major problem with part of the testing done in the Tom's Hardware article as compressing exe & dll files can also cause a major slowdown if they need to be moved into paged memory... ...the problem being that the testing done (both opening & closing a couple of programs & running artificial b/ms) is highly unlikely to have caused this to happen whereas, in a real life multitasking situation using large programs, it's a much more likely occurrence. Anyway, overall i agree with .//TuNdRa; just not about a couple of the specifics.
I think on a fast enough SSD, the difference is not very noticeable. I've been using Drive Press (http://www.magicrar.com/drive-press.html) because it frees up more space on my drive compared to built-in NTFS. I end up saving significantly more space than Windows itself allows. Maybe that is also the reason why my slow-down is not as bad (more spare area on the drive). I have two 600 GB Intel SSDs on my system - one of them for my source codes, the other for my games. VMs are hosted on both SSDs (there's no RAID involved). The raw capacity of the SSDs is 558 GB. Both drives have 100 GB free space. The source code disk has 650 GB actual usage, the games disk has 550 GB actual usage. There is only nominal slow-down on both disks. VMware runs up to four VMs simultaneously and I can do heavy lifting inside them. I think with a SATA III bus instead of the SATA II that I have, the slow-down would be even less noticeable. For regular applications, there is no perceived slow-down at all.
